Effect of PM2.5 on invasion and proliferation of HeLa cells and the expression of inflammatory cytokines IL‑1 and IL‑6

Effects of different levels of PM2.5 on invasion and proliferation of HeLa cells and the expression levels of inflammatory cytokines IL‑1 and IL‑6 under 10 µg/ml PM2.5 were investigated. Different groups of HeLa cells were treated with PM2.5 at 0, 10, 25, 50, 100 and 200 µg/ml for 36 h, respectively. Cell proliferation was detected by MTT assay. Transwell assay was performed to detect the invasion of HeLa cells. Enzyme‑linked immunosorbent assay (ELISA), RT‑qPCR and western blotting were used to detect the expression levels of inflammatory cytokines IL‑1 and IL‑6 in PM2.5‑stimulated HeLa cells. It was observed that proliferation of cells treated with PM2.5 at a concentration of 10 µg/ml was basically the same as that of untreated cells, while high concentration of PM2.5 inhibited the proliferation of HeLa cells in a dose‑dependent manner in the range from 25 to 200 µg/ml (p<0.05). Transwell invasion assay showed that the number of migrating HeLa cells stimulated by 10 µg/ml PM2.5 was significantly greater than that of NC group cells (p<0.05). Western blotting showed that IL‑1 and IL‑6 protein expression levels in HeLa cells after stimulation with 10 µg/ml PM2.5 were significantly higher than that in NC group (p<0.05). RT‑qPCR results also showed that IL‑1 mRNA and IL‑6 mRNA expression levels in HeLa cells stimulated by 10 µg/ml PM2.5 were significantly higher than those in the NC group (p<0.05). Additionally, ELISA results showed that IL‑1 and IL‑6 levels in HeLa cells stimulated by 10 µg/ml PM2.5 were significantly higher than those in NC group (p<0.05). We conclude that high concentrations of PM2.5 can inhibit the proliferation of HeLa cells to a certain extent. Stimulation with 10 µg/ml PM2.5 increases the inv­asion ability of HeLa cells and promotes the expression of inflammatory cytokines IL‑1 and IL‑6.